Partially clogged! Y-THINK-Y
Having no catalytic converter installed is illegal and can cause a myriad of problems. Probably not a backfire though.
Timing belt
catalytic converter
So you can efficiently burn unleaded gas.
Engine mounts
It could be your catalytic converter... yes, catalytic converters clog on these often. its fairly easy to unbolt it from the exhaust manifold. if you take it off, shine a flashlight up from the bottom, you should be able to see light from the top.
A bad catalytic converter will cause a severely restricted exhaust system. You would notice a lack of power and performance from you vehicle and in cases of a completely blocked converter, the engine may not run.
A defective catalytic converter can do that.
If the converter is partially clogged it can cause the engine to overheat which can cause serious problems. Other than that if will not harm the engine.
The converter is plugged and needs to be replaced
the answer is no . the converter would not affect just one cylinder .
No, that would have no effect on the heater system.